Floor slab



1937- E. D. C(IDDDINGTO'N 2 L FLOOR SLAB Filed Sept. 3, 1935 2 Shegats-Sheer. 1

Feb. 23, 1937. CODDINGTON 2,071,455

FLOOR SLAB Filed Sept. 5, 1955 2 Sheets-Sheet 2 Ow/27 a Jam/7 2 fmmm Patented Feb. 23, 1937 iiNiTED STATES.

PATENT orrlcs FLOOR SLAB Edtvzin 1). m1

Wiaassiznor wankee, v Reynolds Corporation, New York, N.. Y, a corporation of Delaware Application s, 1935, Serial No. ram '1. Claims. (Cl-1H8) building structure. More particularlmythisinvention relates to heat insulating building slabs which are capable of being incorporated into building structures by being secured to the building joist or studs by means of nails or other penetrating f elements. The slabs are particular theioistsandstudsdescribedinmycopendins applications Serial Nos; 39,023 to 39,035 inclu sive; 39,02! to 89,029 inclusive: and 47,865 to 47,867, inclusive. An object ofthis invention is the provision ofaprecastcompositionslabhavingaflain faceserving asatreadsurface,andwhich may,

sistant material or ornamental veneer, and an undulated face, the ribs of which provide strengthening ridges extending between oppositeedgesoftheslab. k

The invention contemplates the provision of such a, slab in, which a reinforcing fabric is secured along the undulated surface with portions thereof imbedded within the ribs, thereby giving the elements of the slab resisting stress the maximum leverage obtainable in a slab of a given depth.

The invention: further contemplates the provision of a slab composed .of a cementitious ma- .terial "and .a reinforcing fabric which mar:

the property which allows it to be nailed in place while. being composed of such'cementitious ma terial having slight insulating properties, has extremely high heat insulating and fire resistant properties when .foil is employed in its construction. g A

The slab of this invention in its preferred form isncn-combustible, resistant to decay and free from damage or injury by destructive insects and, when in position -upon supporting tion will be apparent from the following dely suited for use in connection withif desired. be covered with a strip of wear re-.

tailed description when considered in connection with the accompanyin drawl ss wherein:

l is a perspectiveview of slabs madein. accordance with this invention nailed into position upon a series of joists; I 5

Fig. 2is a perspective view, bottom up, of one end of the prwent composition floor slab illustrating the reinforcing fabric;

Fig. 3isavertical cross-'sectionaiviewtbmush two abutting slabs illustrating the manner in m which they are bled in a floor structure;

Fig.4 isaview ofaportion oftheslabshown. in Fig. 2 butin reversed position, showing its tread surface provided with a facing of veneer;

and u Fig.5-isa veviewofaportionofa .slabmad'ein cewiththisinventionpartiallybroken awaytoshowthemannerofconstruction.

Inreferringtothedrawingsindetailthenu- 20 metal ll designates a flat block of cementitiom materialhavingaplane face ll,designedtoconstitute itstreadsurface, and an undulated face I! adapted to form its supporting surface. The

,unduiated face I! provide a series of parallel teristic spring'y property of the cementitious 'material .which .is desirable in composition floor slabs designed to takethe place of wood. The cementitious composition I prefer to utilize for the manufacture of the slab comprises a wet mixture ofgypsum, Portland .cement and sawdust represented approximately in the proportions,- by weight, i20:9.. The material while plastic is easily molded and'upon dryin out it sets into 5 a relatively hard mass. By reason of the sawdust component it possesses a give similar to wood and is capable of being nailed and sawed without. craeking or crumbling. I have found that a nail which has been driven into a slab 5 made in accordance with this invention resists withdrawal to a much greater extent than does a nail which has been driven into a cementitious material in which slagor shale or gritty material was used as an aggregate.

backing sheet I: and the series of reinforcing 10 wires l8, thebars-being embedded within and extending lengthwise along alternate ribs l3.

Relatively large wires or rods I8 are embedded within the cementitious material It preferably immediately adjacent the outer or tread surface 15 thereof, and these rods, like'V-shaped bars l'l, "extend throughout the length of the slabs into which they are incorporated whereby in the use of the slabs in the' .manner illustrated in Fig. 1.

a contra fiexure is produced as will be more fully 20 hereinafter referred to.

To permit ready assembly of the adjacent slabs V in interlocked engagement, opposite edges of the slabs parallel to the ribs ii are cut on an offset so that two upright walls is and 20 connected by 2 an inclined step 2| are formedininverse relationship at each side of the structure. Such arrangement permits the slabs to be placed in abutting position with the extended wall 20 of one slab fitted into engagement with the reentrant wall i9 30 of the other slab with the walls 21 extending in overlapped relation, as illustrated in Fig. 3. Rib

it upon the undulated face of the slab which lies adjacent the wall I [is flattened as "at 22 to insure a better registry of the undulated surfaces of the 85 abutting slabs.

\ In the preferred form of slab backing sheet I! is formed of the stiff paper as above set forth but it also comprises a thin layer of bright metal foil 23 which is affixed to its exposed surface 4 which in normal use is directed toward its supporting members; As shown in Fig. 4 when the slab -is used in fioor constructiomthe wearing surface of the slab may be protected by a facing 24 of veneer or linoleum, orthe usual wooden v is flooring, so as to present a pleasing'appearance or to provide a renewable wearing surface.

The slab, because of the stiffening effect imparted by both the transverse wires and the longitudinaliy extending reinforcing bars and rods.

60 is exceptionally strong due to the positioning of therespective elements even when constituted of a relatively small amount of material; while the insulating property of the metallic foil, reduces heat losses resulting from absorption by and con- 56 duction of heat through the slab and into the.

. supporting structure. Since in normal floors or walls the heat which is conducted into the sup-'- 60 room space when such space has become cooler than the structure, the present slab by retarding, conduction of heat into the supporting structure, overcomes the problem heretofore encountered. v The slab may be cast in any convenient sizes or as shapes, and, if desired, the interlocking joint de-' scribed above may be provided upon all four .edges of the slab, or other types of joints may be adopted.

In the formation of the slab of this invention 70 the fabric, as shown more particularly in Figure 5, is placed into the bottom of a form with the foil on its lower side. A cementitious materialcomprised of gypsum, Portland cement and sawdust, approximately in the proportion, by weight, 7 55:20z9 is mixed and wetted andtben d p ted upon the fabric and thoroughly worked into the spaces between the wires, rods, and bars and the backing sheet in such manner that the bars and the portion of the wires which pass through the ribs are completely embedded in the cementitious 5 material and the backing sheet due to its rigidity is firmly adhered to the cementitious material.

. Just prior to the filling of the form to the desired level depending upon the thickness of the slab to be produced, rods l8 are placed upon the cementitious material in the form in a direction parallel to the ribs and the slab is built up to its I desired thickness with'the material being worked around the rods-so that they are securely embedded in' the finished slab near its surface oppo- 16 site to the fabric. The cementitious material sets'rapidly and may therefore be removed from the forms after a relatively few minutes.

The slab after curinglfor a short period is ready for transportation to and incorporation into a building structure. Said slabis capable of being sawed and fastened in position by penetrating elements. I

In using slabs made in accordance with this invention in the manner shown in Figure 1, joists v25 24 are utilized and these joists may be fabricated in accordance with the disclosure of my copendingapplication Serial Number 39,025. As shown the slabs are formed to extend over two spaces forming a continuous beanrover three supports. When placed in this manner and subjected to load there is a reversal of the bending stress over the center support which is resisted by rods ll thus reducing the effective length of the space which the slot has to span to the distance between the point of contrafiexure to the joist supporting the end of the slab.

The slabs are nailed directly to the joists in a manner which will permit the abutting of adjacent slabs thereagainst both in a direction longi- 40 tudinally of the joists and transversely thereof.

' It will be understood that the preferred embodiment of the invention described above is merely exemplary and that the invention is obviously capable of embodiment in other forms 4 than that described.

I claim: 1 a

l. A prefabricated fioor slab comprising a molded block of cementitious material having a plane face and an undulated face defining a series of parallel ridges, and a plin'ality of reinforcing members disposed adjacent the undulated face'of the slab and extendingcrosswise -of and intersecting the ridges.

2. Afioor slab comprising a molded block of 55 cementitious material having a plane face and I an undulatedface defining a series of parallel ridges, a backing of stiff flexible material secured to the undulated face, a plurality of reinforcing members extending crosswise of and between the '00 ridges, and a plurality of rods extending parallel to the ridges and adjacent to the plane face of the slab. A

' 3. A prefabricated floor slab comprising a generally fiat molded block of cementitious material havinga plane face and an undulated face defining a series of parallel ribs, a backing of stiif flexible material secured to the undulated face.

a pliu'ality of reinforcing wires passing transversely through the ridges between opposite ends 7 of theblock, and a plurality of reinforcement bars entirely embedded within the ribs and extending throughout the length thereof, thereby giving to the elements resisting stress the msximum leverageobtainable in the slab. 1s

. 9,071,455 4. A prefabricated flodr slabcomprising a g erally flat molded block of cementitious material having aplane face and an undulated face defining a series of. relatively closely spaced parallel ribs, a plurality of reinforcement bars entirely embedded within the ribs and extending throughout the length thereof, a'sheet offlexible material secured to the undulated face of the'block and a wear strip of a different material from the slab aiilxed to its plane face. 5. A prefabricated fipor slab comprising a gen-\ erally flat molded block of cementitious material, said block being of rectangular outline and having a plane face and an undulated face defining a series of relatively closely spaced parallel ridges,

a plurality of reinforcing members extending, crosswise of and intersecting the 'ridges inter-, mediate theirheight, a pluralityzof' reinforcing bars extending within the ridges adjacent the crests thereof one of the edges ofsaidblock having a tapered overhanging tongue coincident with the planeface of the block and. the opposite edge r saidblocl: being provided with an undercutreceds of a crossesectional shape corres'pcmi ing to. the tonguejwherebyi adjacent slabs may be assembled in interfitting relationship."

.6. A- prefabricated floor slab comprising a "molded block ofcementitious material having a plane race and ari undulated face defining a series of relatively closely spaced par'alleL ridges, and

.a plurality ofreinforcing bars extending within the=ridges,;saidundulated face being substan- 10 tially entirely ,covered with a heat reflecting.

out' of contact with the biock intermediate 'the 20 ribs.'

EDWIN D, CQDDINGTQN. 

